Hydrocarbon-vapor-burning apparatus.



No. 707,50 Patented Aug. 19, I902.

A. a. MACKLIN.

HYDBOCARBON VAPOR BURNING APPARATUS.

(Application filed Dec. 11, 1900. Renewed June 18, 1902.)

(No Model.) 4 Sheets-Sheet l.

"i m nea'wew. 74

Patented Aug. l9, |902..

No. 707,517. V A. B. MACKLIN. I

HYDROGABBON VAPOR BURNING APPARATUS.

(Application filed Dec. 11, 1900. Renewed June 13, 1902.) (Na Model.) 4 Shaots-Shaet 2.

'///Iaii 50 1 7,2

Hillllllllll Patented Aug. l9, I902. A. B. MACKLIN. HYDRUCABBUN VAPOR BURNING APPARATUS.

(Application filed Dec. 11, 1900. Renwad June 13, 1902.)

4 Sheets-Sheet 3.

(No Model.)

4r .J 7 oh w m v m 8 W 4 W y W I ma a a 2 ,7 o 0 I. a v m No. 707,5!7. Patented Aug. 19, I902.

A. B. MACKLIN.

HYDROCARBON VAPOR BURNING APPARATUS.

(Application filed Dec. 11, 1900. Renewed June 13, 1902.)

(llo Model.) 4 Sheets-Sheet 4.

25 above-named patent, No. 654,408.

llniiTnn STATES PATENT ()FFICE.

ATIIOL B. MACKLIN, OFBROOKLYN, NEl/V YORK.

HYDROCARBON=-VAPOR-BURNING APPARATUS.

SPECIFICATION forming part of Letters Patent No. 707,517, dated August 19, 1902. Application filed December 11, 1900. Renewed June 13, 1902. Serial No. 111,577. (No model.)

and State of New York, have invented certain new and useful Improvements in Hydrocarbon-Vapor-Burning Apparatus, of which the following is a specification.

My present invention is in the nature of an [O improvement upon the apparatus covered by Letters Patent of the United States No. 654,408 granted to me July 24, 1900; and the object of mypresent invention is to improve the construction and operation of the apparatus cov- I 5 ered by said patent.

It is very important to the proper operation of vapor-burning apparatus that the vaporsupply nozzle of the vaporizer be kept clear of the natural accumulation of carbon deposit which is carried into the small orifice of the nozzle by the vapor-current passing therethrough and tends to clog the same. For this purpose it is usual to employ an internal needle, such as is shown and described in my Such a structure is, however, objectionable, not only because it is expensive to make and maintain, but because the great heat of the vaporizer soon anneals the needle and so Weak- 0 ens it that the slightest pressure will cause it to bend and end its usefulness. These internal needles therefore give constant trouble and expense. I propose to overcome this objection to vapor-burning apparatus by pro- 5 viding an external nozzle-cleaning needle which is movably mounted upon the apparatus in such a way that it can be moved into position above the vapor-nozzle andbe inserted in the orifice of the nozzle for clearing the same and then be withdrawn from the nozzle and moved away from the nozzle outside of the zone of greatest heat from the vaporizer. Such an arrangement of the needler can best be used with the style of appa- 5 ratus set forth in my above-named patent, in

so needler.

Another feature of importance in my present invention is the structure of the vaporizer proper, which insures a more effective and a more uniform supply of vapor to the mixing-chamber. I construct my improved vaporizer of an outer tubular section, against which the heating-flame is directed, and a bell-shaped section arranged concentrically within the outer section and having communication wi th the vaporizing chamber or space between them of annular cross section through suitable ports or openings adjacent to the base of the inner section. lhe fuel (hydrocarbon oil, such as ordinary kerosene) is supplied through a suitable tube to the base of the inner bell-shaped section and passes therefrom into the annular vaporizingchamber, the pressure for supplying the oil causingthe air in the crown or top of the bell-shaped section to be compressed slightly. The thin'film of oil rises in the vaporizingchamber and is quickly vaporized by coming in contact with the heated surface of the outer wall of the vaporizer and issues at the nozzle in a steady stream of vapor, the cushioning effect of the compressed-air column serving to equalize the pressure of the vapor stream and prevent the possibility of oil under high pressure being projected suddenly into the upper part of the vaporizer and spitting through the nozzle, causing what is known as a fiare-up.

My improvements in vapor-burning apparatus have been designed primarily for a hanging vapor lamp, which is adapted to be coupled to and supported by the ceiling-tip of the ordinary gas-supply pipe of a dwelling. WVith this application of my improvements I employ permanent gas-pilots for lighting the burners and a gas Bunsen (lighted by a permanent gas-pilot) for creating the initial heat in the vaporizer. I employ the vertical arrangement of the vaporizer and mixingehamber with an air-supply space between them, as set forth in my above-named patent, and to avoid the possibility of the products of combustion of the auxiliary vaporizer-heating burner being drawn into the mixing-chamber by the vapor-blast I surround the said auxiliary burner with a cup-shaped shield or deflector.

To facilitate getting at the lamp proper for repair or adjustment, I provide a novel form of globe-support, by which the globe may be lowered from around the lamp and supported in lowered position or be raised around the lamp and supported in raised position.

In order that my invention may be fully understood, I will first describe the same with reference to the accompanying drawings and afterward point out the novelty with more particularity in the annexed claims.

In said drawings, Figure 1 is an edge elevation, partly broken away, of my improved vapor-burning apparatus. Fig. 2 is an enlarged side elevation, partly in section, of the main parts of thesame. Fig. 2 is a detail view illustrating the arrangement of the wiregauze strip in the mixing-chamber. Fig. 3 is a detail sectional plan view of the improved needling apparatus. Fig. 3 is a detail projection of part of the needler supporting and guiding tube, showing the guide-slot. Fig. i is an elevation, partly in section, of asingleburner lamp embodying my improvements. Fig. 5 is an elevation, partly in section, representing a heating-burner embodying my improvements. Fig. 6 is an elevation, partly broken away, showing part of a portable lamp adapted to embody my improvements.

As stated above, the form of my improved vapor-burning apparatus has been designed particularly for lighting purposes in the form of a hanging lamp, which may take the place of the ordinary chandelier for lighting a room, and it may be suspended from the ordinary gas-pipe with which buildings are equipped;

- but, as hereinafter pointed out, I do not limit myself to this adaptation of my invention.

1 indicates the main supporting tube or pipe of my improved lamp.

2 is an ordinary threaded coupling for securing the pipe 1 to the projecting ceiling-tip of the ordinary gas-pipe.

3 is a double-armed bracket adjustably mountedupon the main pipe 1 by means of the set-screw 4, and 5 and 6 are tubes mounted in the ends of the bracket-arms 3 and depending therefrom. At the lower ends of the tubes 5'and 6 are secured the guide nuts or collars 7 and 8.

10 is a globe-supporting ring upon which is mounted the globe 11, held in place by the thumb-screws 12. The ring 10 is secured to the lower ends of slide-rods 13 by means of nuts 14., which rods 13 extend up into the tubes 5 6 and are provided at their upper ends wit-h locking dogs or fingers 15, which are journaled upon the reduced ends of the guide rods 13 and :are adapted to be placed in line with the guide-rods to allow the guide-rods to move vertically in the tubes 5 and 6 or to I be placed at right angles to the guide-rods to engage the upper ends of the tubes and support the guide-rods and connected globe-sustaining ring 10 in elevated position. Just below the upper ends of the guide-rods 13 are mounted adjustable collars 16, which slide freely within the guide-tubes 5 6 and are adapted to engage the nuts 7 8 at the lower ends of said guide-tubes and sustain the globe-sustaining frame when it is moved to its lowered position. The purpose of this vertically-movable globe-supporting frame is to enable the operator to lower the globe from around the lamp when he desires access to the lamp for adjusting or repairing any oi. the parts.

is an ordinary dished reflector mounted upon the main supporting-pipe 1 between suitable washers 21 22, secured in place by nut 23, threaded upon the upper end of pipe 1. The lower end of the supporting-pipe 1 is bent slightly to one side at l, as shown in Fig. 1, to enable the placing of the lamp proper centrally within the globe-supporting frame. The vapor-lamp proper comprises, essentially, a suitable vaporizer, a mixingchamber, and burners connected with the mixing-chamber.

25 is a central ring or casting from which extend the upwa rd'ly-curved burner-tubes 26, which terminate in the burners 27. The central ring or casting 25 is formed with an integral yoke 30, which is shaped to fit snugly against the lower end of the supporting-pipe 1, to which it is secured by means of the clip or yoke 31, engaging the pipe 1 and secured to the yoke by means of set-screws 32. The ring or casting 25 constitutes the base portion. of the mixing-chamber.

is the bell-shaped upper and outer portion of the mixing-chamber, which is mounted upon the ring 25.

36 is the tubular inner part of the mixing chamber, formed with open upper end 37 and open lower end 38. This inner tube 36 is adjustably and removably supported within the bell-shaped outer section 35 by means of the threaded connection 39 with the lower wall of the base ring or casting 25. Adjacent to the upper end of the inner tubular section 36 are formed openings 40. The inner tubular section may be provided with a piece of wiregauze 41, which is slit transversely at its air as they pass through the mixing-chamber. The combined vapor and air passes through the open end 37 and openings 40 of tube 36 through the wire-gauze out into the bell-shaped outer section 35 of the mixingchamber.

50 indicates two short tubular sections threaded into openings in the lower face of the casting 25 and supporting at their ends the ring or casting 51 of the auxiliary burner, which surrounds and supports the vaporizer, which I will now describe. The vaporizer comprises an outer tubular section 60, having at its upper end avapor-nozzle 61 and at its lower end a threaded plug 62, upon which is supported an inner bell-shaped tubular section 63, closed at its upper end 64-. The inner tubular bell-shaped section 63 is provided adjacent to its base with a series of small ports or openings 65, which afford eommunication between the inner and outer chambers of the Vaporizer.

66 is a fuel-supply pipe leading into the inner tubular section 63 of the vaporizer. The vaporizer is supported from its upper or nozzle end, the nozzle 61 having one or two coarse screw-threads at 61 which screw into the central opening of the crown of the burner-ring 51. These means of mounting the Vaporizer render it possible to remove the vaporizer for repair, which is an important practical consideration. it The auxiliary burner for maintaining the vaporizer at the proper heat consists of a small ring-burner similar to the auxiliary burner disclosed in my above-named patent, of which ring 51 is a part. A cone-shaped wire-gauze 67 is held within the burner-ring 51 by means of the ring 68, having a central opening to allow the proper spread of the flame around the vaporizer. To prevent the products of combustion from the auxiliary burner 67 passing up into the mixing-chamber of the lamp under the action of the current of vapor from nozzle 61, I surround the auxiliary burner with a shield 69,which is supported upon the burner-ring 51 by ring 68. As stated above, my improved needler for keeping clear the orifice of the vapor-nozzle is exteriorly arranged, as distinguished from the common form of needling devices. Formed integral with one of the burner-tubes 26 is a socket 70, within which is adjustably secured a depending guide-tube 71,formed with an angular slot 72 73, extending vertically and horizontally of the guide tube.

70 is a set-screw for securing the tube 71 in the socket 7 O.

is the needle-operating rod, formed at its upper end with a curved arm 76, in the outer end of which is a needle-supporting opening 77 and a small set-screw 78, arranged to secure the needle 79 in its opening 77. The upper end of the needle-operating rod 75 is mounted within the tube 71, the arm 76 extending through the slot 72 73, as shown in the drawings.

71 is a hand-wheel upon the lower end of rod 75, by which the needler is operated. The tube 71 is so adjusted in its sockets 70 that the vertical portion 7 3 of its slot will be presented toward the vaporizer-nozzle 61, so that when the needle-operatin g rod 75 is rotated in the tube 71 the arm 76 will travel in the horizontal portion 72 of the angular slot until it reaches the vertical portion 7 3 of said slot, when the needle 79 will be presented directly above the orifice of the vapor-discharging nozzle 61. The needle-operating rod 75 can then be pulled downwardly, the arm 76 sliding in the vertical portion 73 of the slot and the needle 79 entering the orifice of the nozzle 61 to clear it of any deposits.

It is essential to the production of a'practical needling device that the needle and its supporting and operating arm be readily detachable from the lamp for adjustment or repair. For this purpose I extend the horizontal portion 72 of slot (in tube 71) into a slight vertical offset 72, which leads into a long vertical slot 72*, extending to the bottom of the supporting-tube 71, as shown in projected View, Fig. 3. The shoulder formed by the offset 72 will normally limit the rotation of rod 75 and arm 76 (when the needle is moved away from the nozzle) by reason of the engagement of arm 76 therewith. WVhen, however, it is desired to remove the needle supporting and operating device, the rod 75 is moved upwardly from the stated inoperative position, causing arm 76 to travel in offset-groove 7 2 and is then rotated slightly to bring arm 76 into the long vertical groove 72, when the rod 75 and arm 76 can be pulled downwardly and out of the supporting-tube. The needling device is replaced in its supporting and guiding tube by a reversal of these movements. The importance of this form of needling device is due to the fact that the needle can be normally supported outside of the zone of greatest heat from the vaporizer and can at will be moved into position to clear the orifice of the vaporizernozzle. With this form of needling device it is important that an open space be provided between the vaporizer and mixing-chamber for the free movement of the needle into and out of operative position.

80 is an ordinary incandescent mantle supported upon a rod 81, which is adjustably mounted in the ring 82, surrounding the burner 27.

83 84C are small gas-pilots mounted upon small branch tubes 85, connected through an offset 86 with the main supporting gas-pipe 1.

90 is a gas Bunsen mounted at the lower end of the branch pipe 91, leading from the lower end of the main supply-pipe 1.

92 is a cock controlling the supply of gas through pipe 91 to the Bunsen burner.

93 is a gas-pilot supplied from the pipe 91 and supported in position to ignite the Bunsen burner 90. It will be observed that the Bunsen burner 90 is arranged to direct its flame against the outer wall of the vaporizer (30.

It is myintcntion to apply my lamps to the ordinary gas-pipes now in use in dwellings and to utilize the ordinary illuminating-gas to maintain the lighting-pilots 83, 84, and 93 and to supply the gas Bunsen 90. The gas Bunsen 90 is lighted to obtain the initial heat of the vaporizer for starting the lamp, and it is my intention to shut off the gas Bunsen immediately after sufficient vapor has been generated to supply the auxiliary burner, which maintains the vaporizer at its proper vaporizing temperature while the lamp is in operation.

The main feature of the vaporizer, as above described, consists in forming it of inner and outer tubular sections, which aflford a vapo- IIO .rizing-chamber of annular cross-section, the .value of which is due to the relatively large area of heating-surface to which the fuel is exposed. I

A further advantage of my improved vaporizer is due to the cushioning eflect of the inner bell-shaped section, which provides a cushion of compressed air to cause a uniform how of fuel to the vaporizing-chamber, said .in the flame.

As stated above, my improvements have primarily been designed for a hanging vapor- I lamp; but some of the features of theinven- .have hereinbefore described.

tion are also applicable to other forms of lamps, as I will now explain.

Referring to Fig. 40f the drawings, it will be observed that I have illustrated my improvements applied to a single burner bracket-lamp which is adapted to be attached to and supported by the ordinary gas-pipe bracket now commonly used in dwellings.

100 indicates the bracket gas-pipe, having the ordinary cock 101, and 102 is a verticallyextending pipe joined at 103 to the bracketpipe 100 and supporting at its upper curved .end my improved single-burner lamp. This single-burner lamp has many features in common with the double-burner lamp which I In this form of a lamp I employ the described vaporizer 60, having fuel-supply pipe 66 and vapor-discharge nozzle 61, the annular vaporizer-heating burner 51, the deflector 69, and the nozzle-needler 79. The globe 11 rests upon a globe-supporting ring 104, sustained bya suitablebracket 105, surrounding and resting upon the ring-burner 51. The main diiference between the single-burner lamp and the double-burner lamp is in the construction of the mixing-chamber. This mixing-chamber comprises an inner vertically-adjustable tube 110, threaded into the bottom wall of the central ring or casting 111. The upper end of the inner tube 110 is formed with a series of deep cuts or notches 112, the dividing-walls of which form vertical ribs 113, upon which rests the mixing and deflecting cone 114, the point of which rests centrally within the tube 110. The outer wall 115 of the mixing-chamher is of tubular shape and is supported within the base ring or :casting 111 concentrically with the inner tube 110. The tubular outer wall 115 has an inwardly-curved portion 116, from which extends the contracted'burnertube 117, which terminates in the burner proper, 118. A bracket-ring 119 surrounds the burner-tube 117 and supports a mantlerod 120 in the usual manner. The mixingchamber is supported above the vaporizer with a free air-supply space between the vapor-nozzle 61 and the inlet of the mixingply tube 125 is also extended Vertically and supports a permanent gas-pilot 126, by which the burner 118 is ignited.

The singleburner vapor lamp which I have just described operates in the main the same as the double-burnerlamp. (Illustrated in Figs. 1, 2, and 3.) I have found, however, that the specific construction of the mixingchamber just described is very important for this single-burner lamp. The arrangement of the inner tube 110, having the cuts or notches 112 and the centrally-supported deflector and mixing-cone 114, cooperates with the inwardly-curved portion 116 of the outer wall of the mixing-chamber to effect a perfect mixture of the air and vapor, so as to produce a satisfactory inflammable lightinggas.

In Fig. 5 I have shown a further slight modification of my invention to adapt it to a heater. In this application of my invention the vaporizer and mixing-chamber are practically the same as just described in Fig.

4. The upper contracted portion of burnervtube 117 of the mixing-chamber in this form,

however, terminates in an enlarged burnerrose 130, having a central cone-deflector 131,

projecting downwardly from the center of the burner. I have found this slight modification of my invention to be very elfective as a heating-burner. My improvements may also be satisfactorily applied to a portable lamp. I have shown in Fig. 6 the base portion of such a portable lamp in connection with which my improvements may be used. In this figure, 135 represents a globular tank or font having a suitable supporting-base 136. In the central opening 137 is fixed a collar 138, into which is threaded a valvebody 139, through which is formed a passageway 140, controlled by the pin-valve 141, threaded into valve-body 139 and held in place by the cap 142, which is adapted to confine a suitable packing around the valvestem.

142'" is a ring or washer surrounding the stem of valve 141 and held in its recess 142 by the packing and cap142. The ring or washer 142 confines the movement of the pin-valve and prevents its removal without first removing the cap.

143 is the ordinary alcohol-cup surround.- ing the lower end of the vaporizer 144, which is threaded upon the valve-body 139. The

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vaporizer and mixing-chamber and lightingburner are of the same construction as illus trated in Fig.

145 is another opening in the lamp-font 135, into which projects the internally-threaded collar 146, formed with an air-port 147, controlled by a hollow pin-valve 148. 149 is an air-pump of ordinary construction arranged to compress air in the tank or font 135.

150 is a tube projecting from the valve-body 139 down into the lamp-font 135 and supporting at its lower end an oil-strainer 151 of ordinary construction, which is supported just clear of the bottom of the font 135.

It will be observed that the collar 146 is extended into the font 135. This is for the pur-- pose of preventing the filling of the tank beyond the dottedline :r, it being necessary to have an airspace above the oil for the proper operation of the lamp. YVhen it is desired to operate this portable lamp, the lamp-font being filled to the dotted line 00, it is only necessary to compress the air above the oil by means of the air-pump 149 and then start the lamp by lighting the alcohol in the cup 143 and later opening the valve 141. The pressure of compressed air above the oil forces the oil in a regular stream up through pipe 150 and valve-body 139 into the vaporizer,

where the oil is vaporized and fed into the mixing-chamber, from which the inflammable mixture passes into the burner in the manner well understood. The lamp may be extinguished either by closing the valve 141, and thereby shutting off the supply of fuel, or by opening the valve 148, thereby relieving the la1np-font of its air-pressure.

Having thus described my invention, the

following is What I claim as new therein'and desire to secure by Letters Patent:

1. In a vapor-burning apparatus, the combination of a mixing-chamber having an inlet for vapor and air, a burner communicating with the mixing-chamber, and a vaporizer having a fuel-supply and a vapor-discharge nozzle arranged adjacent to and separated from the mixing-chamber with a free air-space between the mixing-chamber and vaporizer, with a movably-mounted nozzle-clearing needling device located exteriorly to the vaporizer and mixing-chamber,said nozzle-clearin g device carrying a needle which is normally supported away from the vapor-nozzle in the vaporizer, and a movable support for said needle, mounted upon the exterior of the apparatus, whereby the needle may be moved into and out of operative relation with the nozzle, and be supported normally outside the zone of greatest heat, substantially as set forth.

3. In a vapor-burning apparatus, the combination of a mixing-chamber, avapor-burner communicating therewith, and a vaporizer having a fuel-supply and a vapor-discharge nozzle, with a nozzle-cleaning needle, and a horizontallyrotatable and vertically-movable support carrying the nozzle-needle, said needle-support being mounted upon the exterior of the apparatus at a point removed from the zone of greatest heat, substantially as set forth.

4. In a vapor-burning apparatus, the combination of a mixing-chamber, a vapor-burner communicating therewith, and a vaporizer having a fuel-supply and a vapor-discharge nozzle, with a nozzle-needle, a rod or bar having an arm extending from it in which the needle is mounted, a support for said rod or bar, a horizontally and vertically extending guide groove or slot on one of said parts and a projection on the other engaging said guide groove or slot, whereby the rod or bar may be rotated and moved vertically upon its support, substantially as and for the purpose set forth.

5. In a vapor-burning apparatus, the combination of a Inixing-chamber,a vapor-burner communicating therewith, and a vaporizer having a fuel-supply and a vapor-discharge nozzle, with a nozzle-needle, a tubular support having a vertically and horizontally extending guide groove or slot, a rod or bar mounted in said tubular support, and an arm extending from said rod or bar through said guide groove or slot and supporting thencedle, substantially as and for the purposeset forth.

6. In avapor-burning apparatus, the combination of a miXing-chamber,a vapor-burner communicating therewith, a vaporizer having a fuel-supply and a vapor-discharge nozzle, parts connecting the mixing-chamber and vaporizer, whereby one is supported by the other with a free space between them, with a nozzle-needle operating in the free space be-. tween the mixing-chamber and vaporizer, a vertically-movable rotatable supporting-piece mounted adjacent to one of the parts connecting the mixing-chamber and vaporizer, and a curved arm extending from said supporting-piece and carrying the needle and adapted to project around one of said connecting parts to present the needle in proper relation with the vapor-nozzle, substantially as set forth.

7. In a vapor-burning apparatus, the combination of a mixing-chamber, and a vaporburner with a vertically-arranged vaporizer, having a fuel-inlet at its lower end, and a vapor-discl1argo nozzle at its upper end, an

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.an equalizing cushioning-chamber, said inner bell-shaped section communicating adjacent to its open end with the outer tubular section of the vaporizer, a fuel-supply lead' ing to the open end of the inner section, and a vapor-discharge nozzle arranged in the upper end of the outer. section, substantially as set forth.

9. In a vapor-burning apparatus, the combination of a mixing-chamber, and a vaporburner, with a vertically-arranged vaporizer comprising two'tubular sections arranged one within the other and communicating at or near their lower ends, said inner section having a fuel-inlet at its lower end to form an aircushioning chamber, a vapor-discharge noz zle leading from the upper end of the outer section, and means for applying heat to the outer section.

10. In a vapor-burning apparatus, the combination of a mixing-chamber, and a vaporburner, with a vertical vaporizer comprising an outer tubular section, a vapor-discharge nozzle leading from the upper end of the outer section, an inner tubular section closed at its upper end and arranged concentrically within the outer section and having ports or openings adjacent to its base which communicate with the chamber of said outer sec- 5 tion, a fuel-supply communicating with the base of the inner section, and an auxiliary J vapor-burner supported adjacent to the vaporizer and having's uitable vapor communication with'the mixing-chamber, substantially as set forth.. I p

11. In a vapor-burning apparatus, the combination of the vertically-arranged mixingchamber and vaporizer having a free air-supply space between them, a vapor-burner communicating with the mixing-chamber, a fuelsupply and a vapor-discharge nozzle for the vaporizer, an auxiliary vapor burner arranged beneath said free air-supply space adjacent to the vaporizer to heat the same, an exteriorly and movably mounted needling device operating in the free space between the mixing-chamber and vaporizer, and a shield surrounding the auxiliary burner to prevent the products of combustion from being drawn into the mixing-chamber by the Vapor-current, substantially as set forth.

12. In a vapor-burning apparatus, the combination of the vertically-arranged mixingchamber and vaporizer having a free air-supply space between them, a vapor-burner communicating with the mixing-chamber, a fuelsupply and a vapor-discharge nozzle for the vaporizer, an auxiliary Vapor burner sur rounding the vaporizer beneath the said free air-supply space, tubes communicating between the mixing-chamber and said auxiliary burner, an exteriorly and movably mounted needling device operating in the free space between the mixingchamber and vaporizer, and a shield surrounding said auxiliary burner to prevent the products of combustion being drawn into the mixing-chamber, substantially as set forth.

ATI-IQL l3. MACKLIN. 

